Dapagliflozin is an active sodium-glucose co-transporter-2 (SGLT2) inhibitors and is used in the treatment of patients with type 2 diabetes. Dapagliflozin is chemically known as (2S,3R,4R,5S,6R)-2-[4-chloro-3-(4-ethoxybenzyl)phenyl]-6-(hydroxymethy)tetrahydro-2H-pyran-3,4,5-triol OR (1S)-1,5-anhdro-1-C-[4-chloro-3-[(4-ethoxyphenyl)methyl]phenyl]-D-glucitol, having structural formula as represented by formula (I).

Dapagliflozin developed by Bristol-Myers Squibb in partnership with AstraZeneca. Dapagliflozin is marketed in USA under the trade name FARXIGA® and Europe as FORXIGA® in the form of tablets having strengths 5 mg and 10 mg. Dapagliflozin inhibits the transporter protein SGLT2 in the kidneys and thereby reduces renal glucose reabsorption, leading to urinary glucose excretion and a reduction in blood glucose levels.
Dapagliflozin and its pharmaceutically acceptable salts first time disclosed in U.S. Pat. No. 6,515,117. US'117 describes the synthesis of Dapagliflozin (as shown in scheme-1 below) using TMS protected gluconolactone and lithium halobenzene as raw materials to provide intermediate as reaction liquid washed with methanol and directly quenched with a solution of methanesulfonic acid to give methoxy Dapagliflozin. This methoxy Dapagliflozin reacted directly with triethylsilane and boron trifluoride to provide crude Dapagliflozin. The purification has carried out by O-acylating the crude Dapagliflozin in pyridine which upon treatment with LiOH provides amorphous Dapagliflozin as a glassy off-white solid with purity 94%.
This crude Dapagliflozin is purified by acetylating crude Dapagliflozin to (1C)-2,3,4,6-tetra-O-acetyl-1,5-anhydro-1-[4-chloro-3-(4-ethoxybenzyl)pheny]-D-glucitol in pyridine.

Pyridine is toxic in nature and therefore its use as a solvent should be avoided for industrial production of an active pharmaceutical ingredient. Thus, there is a need in the art to develop a purification process for the preparation of Dapagliflozin that avoids the use of pyridine as a solvent. This method also involves O-acylation of the crude compound which unnecessarily increases the reaction steps, is not conducive to improve the reaction yield and also makes the whole process cumbersome.
U.S. Pat. No. 6,774,112 discloses crystalline complexes of C-aryl glucosides with natural amino acids like (L)-phenylalanine and (L)-proline.
U.S. Pat. No. 7,919,598 (10757/DELNP/2008) discloses 1:2 crystalline complex of L-proline (Form 3), 1:1 crystalline complex of L-proline (Form 6), Hemihydrate of 1:1 crystalline complex of L-proline (Form H5-2), 1:1 crystalline complex of L-phenylalanine (Form 2) and their process.
International Publication No. WO2013/079501A1 describes crystalline Dapagliflozin hydrate Form A and Form B and their processes.
U.S.2015/0307540 discloses amorphous form of Dapagliflozin 1,2-propanediol or hydrates thereof.
Though, there are processes available in the literature for the preparation of amorphous Dapagliflozin, still there remains a need for the production-friendly, stable, cost effective and industrially applicable process for the preparation of pure amorphous Dapagliflozin.